On Sat, Jun 28, 2008 at 11:29 AM, Daniel J Blueman<daniel.blueman@gmail.com> wrote:> On Sat, Jun 28, 2008 at 11:11 AM, Vegard Nossum <vegard.nossum@gmail.com> wrote:>> (removed linux-kernel from Cc)>>>> On Sat, Jun 28, 2008 at 2:05 AM, Daniel J Blueman>> <daniel.blueman@gmail.com> wrote:>>> As the mic is working fine, but with this variable DC offset, it felt>>> like something needed tweaking in the mixer (summation) node. I>>> understand more about the node connectivity now, and found muting the>>> front mic mixer input and setting LR gain to 0 at mixer node 23h>>> addresses the issue:>>>>>> (from page 42 at ftp://66.104.77.130/pc/audio/ALC883_DataSheet_1.3.pdf)>>>>>> # ./hda-verb /dev/snd/hwC0D0 0x23 SET_AMP_GAIN_MUTE 0x7180>>>> Are you saying that this fixes the problem completely for you?>> Yes, this addresses the problem squarely. The front mix mixer input is> adding this offset, looks like they have a capacitor between a> reference voltage and the pin or something, so it floats up.>>>> Vegard - your HD bus enumeration looks similar and I'd bet the vendor>>> followed the same Realtek application note, so can you give this a>>> shot too? If not, try mixer node 20h.>>>> I agree. Thanks for the link, I found ALC268 now as well, and I am>> experimenting...>>>> I think 23h is [in]correct -- this is the one with caps f00040h for me too.>>>> But neither of them had any effect at all.>> OK, I'll take another look at the debug output you posted; I forgot> you aren't using the ALC883.